Ratio computing device



Feb. 5, 1946. 13, M BERGEs 2,394,284

. ammo comru'rme nmfxcs Filed Nov. 9, 1943 v w g k WAFER 1:.

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Patented Feb. 5, 1946 RATIO COMPUTING DEVICE Donald M. Borges, Lakewood, Ohio, assignor to Bendix Aviation Corporation, Tcterboro, N. J., a corporation of Delaware Application November 9, 1943, Serial No. 509,623

4 Claims.

My present invention relates to computing devices and more particularly to a mechanism for automatically determining the ratio of one value to another.

An object of my invention is to provide novel means for measuring the ratio between a first and a second value.

Another object of my invention is to provide a novel means for measuring the ratio between the fuel and the air oxygen supplied an internal combustion engine. l P 4 .Another object of my invention isto provide a novel device, including a first biasing means of a predetermined value, a second biasing means of a first value to be determined, and an arm biased by the said first and second meansin op-' posite directions and means for adjusting the first biasing means along the arm for measuring a. second value, together with means for adjusting the second biasing means along the said arm. whereby the ratio ofthe first value to the second value may be readily determined.

Another object of my invention is to provide automatic means for adiustingthe second biasing means in relation to the first biasing means for determining the ratio of theflrst value to the second value. a.

Another object of my invention is to provide novel indicator means operated bythe aforesaid automatic means, whereby theratiobetween the said values may be readily-,determined.

Another object of my invention is toprovide novel adjustable means for varying the position of the aforesaid first biasing means in relation to the second biasing means for adjusting the values thereof.

Another object of my invention is to provide novel indicator means operated by the latter adjustable means for determining the value of a first condition, and other indicator means operated by automatic means responsive to said adjustable means and a second condition responsive means for determining the ratio of the value of said first condition to the value of said second condition. r

A further object of my invention is to provide a compact and efllcient fuel-air ratio determining device for use with an internal combustion engine, and a device of such simplicity in construction as to adapt it for manufacture and installation at low cost.

Other objects and advantages of this invention are set forth in the following description, taken with the accompanying drawing; and the novel features thereof are pointed out in the appended claims. The disclosure, however, is illustrative only and I may make changes in detail, especially in matters of shape, size and arrangement of parts within the principle of the invention to the ;full extent indicated by the broad and general meanings of the terms in which the appended claims are expressed.

In the accompanying drawing the figure is a longitudinal section through the frame of the device showing the operative mechanism in side elevation.

Referring to the drawing, there is shown a frame indicated by the numeral l in which is mounted a straight link or arm 2 having one end pivotally mounted by a pin 3 in a suitable slot 4 formed in the frame I. The opposite end of the arm 2 is pivotally connected by a pin 5 to a link 6. The link 6 is in turn pivotally connected at the opposite end by a pin 1 to one end of a bell crank lever 8 which is pivotally mounted at 9 in a suitable slot Ill formed in the casing I. At the opposite end of the bell crank lever B there is formed a slot ll in which is slidably mounted a pin H for connecting the bell crank lever B to one end of a shaft [3 for operating a servo motor, as will be explained hereinafter.

A slidable member bar or rod it extends across from opposite sides of the frame I and in spaced relation to the arm 2 at one side thereof. There is mounted on the bar M a projecting part l5 having formed therein a channel IS in which is slidably mounted a bearing member or pin H. The pin H has afilxed thereto a collar is. An expansion spring I9 is positioned between the collar I8 and an end 20 of the projecting part l5 for biasing said bearing member l1 into engagement with said link or arm 2 with a predetermined biasing force.

Mounted on the frame I is a second frame portion 2| which is afilxed to the frame i by bolts 22. A second member bar or rod 23 is slidably carried by the frame 2! parallel to the bar N and to that side of the arm 2 opposite the bar N. A second bearing member or pin 24 is biased or urged into engagement with the arm 2 by a flexible bellows 25 carried by the rod 23. The interior of the bellows 25 is connected by a conduit 26 to a determined source of fluid pressure, as for example the air pressure at the air inlet of a carburetor for an internal combustion engine. The conduit 26 extends through a. suitable slot 21 formed in the frame 2| for permitting the longitudinal movement of the bellows 25 within the frame 2! through operation of the rod 23.

Positioned at one side of the frame H is a block 21A in which is formed a channel 29. Leading into the channel 28 at opposite ends are inlet conduits 30 and 3! providing a suitable supply of pressure medium. There also leads from the channel 28 at a point intermediate the opposite ends thereof a conduit 2'9 for returning the fluid medium to the source of said pressure supply.

The control shaft I3 is slid'abLV mounted in: the channel 28 and has provideda pair of spaced pilot valves 32 and 33 for controlling valve ports 34 and 35 leading into a cylinder 36 at the opposite ends thereof. Positioned within the cylinder 38 is a piston 31 affixed at one end of the rod 23 and slldably mounted in the cylinder N. The piston 31 has provided the projecting portion 31A and 313 for limiting the movement of the piston 31 in the cylinder 36 at the' opposite ends thereof. The channel 23 and cylinder 36 are closed by an end plate 38 secured in place by bolts 35. A sealing gasket 41'' is positioned between the end plate 38 and block 21%.

Frcnr the foregoing it willbe readily seen that upon the link 1 being positioned in parallel relationwith rods I 4 and- 2! the control valves 32 and 33 will be'p'ositioned so-asto-close the ports 34 and 35, respectively, as shown in the drawing'. However, upon the biasing force exerted by thebellows 25 increasing sumbiently to bias the link 2 upward in a clockwise direction about the pivot point 3, a counterclockwise movement will be imparted to the bell crank lever B causing the adjustment of theservo valves 32 and 33* toward the right. This adjustment of the'servo valves 32 and 33 will open theport 3"4- to' the-inlet fluid pressurethrough the conduit 39', resulting in abiasing force-beihg exerted on thepiston 31 forcing the' same toward the right, whereby fluid medium tothe right of the piston 31' will be forced through the port 35 intfo'channel' 28* andreturning to=t l"i'e source of fluld' pressure through theconduit 29.

The aldjjistment' of the piston 31 tothe right will in turrr cause a corresponding adfiustment of the bellows 25 and the bearing member 24' toward theri'ght on the-link funtilthe biasing forces exerted by the bearing-members f1 and 2 on tl'i'e link 2 are once again balanced or in equilibrium, whereuponthe- 2- will be re turned toa position in" parallel relation with the; rods [4 and 23 andthe servo valve to' aposition closing ports 34 and 3B. f course upon" a decrease in the biasing force exerted by the bellows 25- anopposite eflect will take place; whereby the piston 31- will be moved toward the left until a balanced condition is once again effected.

Providedat the opposite end" of the rod' 23 from the piston 31 are suitable sc'alemarkings 40 anda suitable pointer mounted inthe frame 2! for registering on the markings M the positionot the rod 23, and accordingly the'position of the bearing member 24 onthe link 2 in relation to th'epivot 3- when the forces exerted by bearing members FT and 24 on the link 2 are balanced. Thus there is indicated on the scale markings 40 the distance from thepi'vot 3 to the point of contact 01'- the bearing member 24 with the lever 2-, asindicated at B;

There are further provided suitable scale markings positionedin a slot 43* formed in the frame I. A pointer 54 is mounted on the slidahle bar N for registering withthe scale marking 42 the position of the bearing member I! on the link 2 in relation to' the pivot 3. Thus there is indicated on the scale markings 42 the distance from the pivot 3 to the point of contact of the bearing member H with the lever 2, as indicated at A.

There is further provided on the bar it a rack 45 operably engaged by a pinion 46. The pinion 45 may be readily rotated by a shaft 4! adjustable through a control knob 48 for longitudinally moving the bar It.

The knob is may be conveniently mounted on a. control box or panel indicated generally by the numeral 48. The knob 48 has provided a pointer 50- for registering with suitable scale markings 5|. The scale marking 5| may be calibrated in terms of the rate of flow of a, fluid fuel medium toan internal combustion engine. Suitable amplifying gearsnot shown may be provided in the control box for imparting the desired rotary movement to the pinion 48 for each unit of movement of the knob 48-.

Thescale markings are so arranged that at the extreme lowest rate of flow of fluid fuel the bearing member IT is positioned at the extreme right position of the link 2. However, it will be'readi'ly seen that with the device in the adjusted position shown in the drawing. an increase in the fuel flow may be indicated by an adjustment of the bearing member If to the left, unbalancing the arm 2 and causing the bearing member 2!, if the air flow remains constant, to be" automatically adjusted to the left through operation of the piston" 31 until arm 2- returns to a. balanced position. Similarly if the rate of air flow orpressure in bellows 25- increases and the fuel flow remains constant an adjustment of the bearing member 21 to" the right will be e'fiected through operation of thepfston' 31.

The bearing member F1 may be manually adjusted' for such increase through the rotary knob 48 in' accordance with the calibrated scale; markings 5| as registered bythe pointer 50. Also the bearing member I! may be manually adjusted through the knobs 5-2 and 53 provided at opposite ends of the bar W in: accordance with the scale markings 42' registered by the pointer 48. Further the bellows ZS-upon anincrease in the biasing force exerted therein, as upon a' rise in the air pressure due to an increase in therate of flow would likewise cause an automatic adjustment in the proper amount to the" right through the action of the servopiston 31''. Thus with the device in' the position shown in the drawing, if the fuel flow decreases, this maybe indicated by adjustment of the bearing member I1 toward the right, and if the airflowremains constant, bearing member 24' under the biasing force of the bellows 25 would, effect a clockwise adjustment of the arm 2, causing the bearing member 2! to be moved by the piston 31 toward the right, until the arm 2 is returned to a neutral position. Further if the air flow decreases, while the fuel flow remains constant, an adjustment of the bearing member 24 would be automatically effected toward the left through the operation of the piston 31.

The operation of the device is based on the fact that for equilibrium the sum of the movements about any point equals zero.

In the instant disclosure the-spring r9 will exert a constant pressure on the lever, link or arm 2 as long as the lever does not move about the point 3. The point of applicatioh of this spring load, or in other words, the distance A can be varied by rack and pinion 45 and 45, as previously explained. If P represents the load' on lever 2 caused by the pressure in the bellows 25, the point of application of pressure P may be varied by movement of the piston 31. If K represents the value of the biasing force exerted by the spring 19, then if K multiplied by the distance A does not equal pressure P multiplied by the distance B, lever 2 will be displaced from its neu-' tral position. a r

Displacement of lever 2 from the neutral position causes in turn displacement of the valve members 32 and 33 from a neutral position. Such displacement of the valve members 32 and 33 then directs a pressure medium so asto' niove the piston 31 in the proper direction, as previously described, so as to adjust the pointof application of pressure P to a point causing the lever 2 to be biased back to the neutral position once again. Such adjustment of the lever 2 will in turn cause the valve members 32 and 33 to close,

, respectively, the ports 34 and 35, whereupon the piston 31 will be locked in the adjusted position, holding the distance B until a change in either distance A or pressure P causes a reoccurrence of the above cycle of operations.

It is, of course, not necessary that the pressure P be obtained from a bellows. Any suitable means for applying a biasing force P to lever 2 that varies with the quantity to be measured may be used.

From the foregoing it will be readily seen that mathematically the following propositions are true:

1. The biasing force applied on lever 2 by the bearing member II=K.

2. The distance from the pivot 3 to the point of application of the biasing force K=A.

3. The biasing force applied through the bellows 25 or other suitable means on the lever 2 by the bearing member 24:1.

4. The distance from the pivot 3 to the point of application of the biasing force P=B.

Then, KA=PB which is the same as Fuel Air and B is a measure of the ratio of fuel to air.

From the foregoing it will be seen that I have provided novel means whereby the ratio of one value to another may be readily determined.

Although only one embodiment of the invention has been illustrated and described, various changes in the form and relative arrangement of the parts, which will now appear to those skilled in the art, may be made without departing from the scope of the invention. Reference is, therefore, to be had to the appended claims for a definition of the limits of the invention.

What is claimed is:

1. A device for indicating the ratio of one value to another, comprising, in combination, a frame, a link having one end pivoted to said frame, a slidable bar carried by said frame and spaced from said link at one side thereof, a first hearing member adapted to be moved by said bar, spring means for urging said first bearing member into engagement with said link with a predetermined force, a slidable rod carried by said frame parallel to said bar and spaced from said link on a side of said link opposite to said bar, a second bearing member in engagement withsaid iink an :expansible bellows carried. by said 'rod,rsaid*second bearing member "being mounted upon said bellows, said bellows being open to fluid pressure-from an air supplyline ioran internal combustion engine, motor means controlledaby movement of said link, and said mbtoi rneans arranged to move said rod and said secondmeann member along-said link in a direction to actuate said link to a predetermined position of balance, first indicator means movable upon motion of said bar for indicating the rate -of supply of a fuei medium to an internal combustion engine, and second indicator means movable-upon motion of said rodto indicate the distance tneasured 1mm the pivot of said link to the point of engagement of said second bearing member with said link when said link is in said predetermined balanced position, whereby the ratio of fuel to air supplied said internal combustion engine may be determined.

2. A device for indicating the ratio of one value to another, comprising, in combination, a frame, a link having one end pivoted to said frame, a slidable bar carried by said frame and spaced from said link at one side thereof, a first bearing member moved by said bar, spring means for urging said first bearing member into engagement with said link with a predetermined force, a slidable rod carried by said frame parallel to said bar and spaced from said link on a side of said link opposite to said bar, a second bearing member in engagement with said link, an expansible bellows carried by said rod, said second bearing member being mounted upon said bellows, said bellows being open to fluid pressure from a determined source, motor means controlled by movement of said link, and said motor means arranged to move said rod and said second bearing member along said link in a direction to actuate said link to a predetermined position of balance, and indicator means movable upon motion of said rod to indicate the position of said rod when said link is in said balanced position.

3. A device for indicating the ratio of one value to another, comprising a frame, a straight link having one end pivoted to said frame, an angular lever pivotally connected to the other end of said link, said lever being pivoted to another portion of said frame, a slidable bar spaced from said straight link on one side thereof, a bearing member moved by said bar, spring means for urging said bearing member into engagement with said straight link with a determined force, a slidable rod carried by said frame parallel to said bar on a side of said straight link opposite said bar, a second bearing member in engagement with said link, a flexible bellows carried by said rod, said second bearing member being mounted upon said bellows, said bellows being open to fluid pressure from a determined source, a servo-motor including a pair of spaced pilot valves connected to said angular lever and a reciprocable servopiston controlled by said valves and connected to said rod, said servo-motor being operated by fluid under pressure upon angular motion of said straight link which is transmitted through said angular lever to said pilot valves to move said second bearing member along said straight link in a direction to move said straight link to a position of balance and restore said pilot valves, and scale means movable upon motion of said rod to indicate the position of said rod when said link is in balanced condition.

4.; A device for indicatingthe ratio of one vazlue to another, comprising in combination, a frame; anarm pivotally connected atone endi to said frame, a first slidable' membercarried by said-v frame and spaced from said arm at one side thereoga first biasing means carried by'said first slidable member, said first biasing means exerting. a force on: said arm at a first point tending to pivot saidarm front abalancecl position: in: one direction about saidpivotedend, a second: siidable member carried by said frame and spaced from said arm at the opposite side thereof, aseeond biasing means carried by said second slick able member, said second: biasing means: exertmg: a force on said arm at a second point tending to pivot said arm from: a balanced position in:

an opposite direction aboiit said pivoted end, said first and seeondrslidable members for varying the relative positions of: said first and second biasing means, motor means controlled by movement of said arm, and said motor means arranged tomove said first slidable member and said first biasingmeans along said arm in a direction to actuate said arm to a predetermined position ofbalance, and' indicator means movable upon motime at said first slidablemember to indicate the position of said first slidable member when saidarm is in' said balanced position.

DONALD M. BERGEs. 

